| First Author | McDuffie M | Year | 2008 |
| Journal | Diabetes | Volume | 57 |
| Issue | 1 | Pages | 199-208 |
| PubMed ID | 17940120 | Mgi Jnum | J:132435 |
| Mgi Id | MGI:3775963 | Doi | 10.2337/db07-0830 |
| Citation | McDuffie M, et al. (2008) Nonobese diabetic (NOD) mice congenic for a targeted deletion of 12/15-lipoxygenase are protected from autoimmune diabetes. Diabetes 57(1):199-208 |
| abstractText | OBJECTIVE: 12/15-lipoxygenase (12/15-LO), one of a family of fatty acid oxidoreductase enzymes, reacts with polyenoic fatty acids to produce proinflammatory lipids. 12/15-LO is expressed in macrophages and pancreatic beta-cells. It enhances interleukin 12 production by macrophages, and several of its products induce apoptosis of beta-cells at nanomolar concentrations in vitro. We had previously demonstrated a role for 12/15-LO in beta-cell damage in the streptozotocin model of diabetes. Since the gene encoding 12/15-LO (gene designation Alox15) lies within the Idd4 diabetes susceptibility interval in NOD mice, we hypothesized that 12/15-LO is also a key regulator of diabetes susceptibility in the NOD mouse. RESEARCH DESIGN AND METHODS: We developed NOD mice carrying an inactivated 12/15-LO locus (NOD-Alox15(null)) using a 'speed congenic' protocol, and the mice were monitored for development of insulitis and diabetes. RESULTS: NOD mice deficient in 12/15-LO develop diabetes at a markedly reduced rate compared with NOD mice (2.5 vs. >60% in females by 30 weeks). Nondiabetic female NOD-Alox15(null) mice demonstrate improved glucose tolerance, as well as significantly reduced severity of insulitis and improved beta-cell mass, when compared with age-matched nondiabetic NOD females. Disease resistance is associated with decreased numbers of islet-infiltrating activated macrophages at 4 weeks of age in NOD-Alox15(null) mice, preceding the development of insulitis. Subsequently, islet-associated infiltrates are characterized by decreased numbers of CD4(+) T cells and increased Foxp3(+) cells. CONCLUSIONS: These results suggest an important role for 12/15-LO in conferring susceptibility to autoimmune diabetes in NOD mice through its effects on macrophage recruitment or activation. |
